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    <p>Jan,</p>
    <p> The idea is that gas-fired water heaters sometimes have a
      chimney that runs from the burner up through the tank. When the
      burner is active then the air/exhaust in the chimney is hot and
      the water in the tank gains a little energy from the
      conduction/convection heat transfer from the chimney air to the
      water. When the burner is not active then the air in the chimney
      is not hot and there can be additional energy losses from the tank
      water to that air. The amount of loss is controlled by a parameter
      that asks what the u-value of the flue is and by the input that
      sets the temperature of the air/exhaust in the flue. If you want
      to deactivate those losses you can set the flue u-value to zero.</p>
    <p>kind regards,</p>
    <p> David</p>
    <p><br>
    </p>
    <div class="moz-cite-prefix">On 2/2/2023 5:48 AM, Böttner, Jan via
      TRNSYS-users wrote:<br>
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        <p class="MsoNormal">Hi,<o:p></o:p></p>
        <p class="MsoNormal"><o:p> </o:p></p>
        <p class="MsoNormal"><span lang="EN-US">I’m using the storage
            tank type 534.<o:p></o:p></span></p>
        <p class="MsoNormal"><span lang="EN-US">This tank has gasflue
            losses, which I don’t quite understand from reading the
            documentation.<o:p></o:p></span></p>
        <p class="MsoNormal"><span lang="EN-US">But the way I understand
            it, it doesn’t apply for the tank I am modelling.
            <o:p></o:p></span></p>
        <p class="MsoNormal"><span lang="EN-US">So I would like to
            deactivate these losses, as they make up for about 10% for
            my energy supply.<o:p></o:p></span></p>
        <p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
        <p class="MsoNormal"><span lang="EN-US">Best regards,<o:p></o:p></span></p>
        <p class="MsoNormal"><span lang="EN-US">Jan<o:p></o:p></span></p>
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      <br>
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      <pre class="moz-quote-pre" wrap="">_______________________________________________
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</pre>
    </blockquote>
    <pre class="moz-signature" cols="72">-- 
***************************
David BRADLEY
Principal
Thermal Energy System Specialists, LLC
3 North Pinckney Street - suite 202
Madison, WI  53703 USA

P:+1.608.274.2577
<a class="moz-txt-link-abbreviated" href="mailto:d.bradley@tess-inc.com">d.bradley@tess-inc.com</a>

<a class="moz-txt-link-freetext" href="http://www.tess-inc.com">http://www.tess-inc.com</a>
<a class="moz-txt-link-freetext" href="http://www.trnsys.com">http://www.trnsys.com</a></pre>
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